/**
* auto-detect the charset of a file used code from http://jchardet.sourceforge.net/; see also:
* http://www-archive.mozilla.org/projects/intl/chardet.html
*
* @param file
* @return a set of probable charsets
* @throws IOException
*/
public static Set<String> detectCharset(File file) throws IOException {
// auto-detect charset, used code from http://jchardet.sourceforge.net/; see also:
// http://www-archive.mozilla.org/projects/intl/chardet.html
nsDetector det = new nsDetector(nsPSMDetector.ALL);
BufferedInputStream imp = new BufferedInputStream(new FileInputStream(file));
byte[] buf = new byte[1024];
int len;
boolean done = false;
boolean isAscii = true;
while ((len = imp.read(buf, 0, buf.length)) != -1) {
if (isAscii) isAscii = det.isAscii(buf, len);
if (!isAscii && !done) done = det.DoIt(buf, len, false);
}
det.DataEnd();
Set<String> result = new HashSet<>();
if (isAscii) {
result.add("ASCII");
} else {
for (String c : det.getProbableCharsets()) result.add(c);
}
return result;
}
public String detectFileCharset(File file) throws FileNotFoundException, IOException {
detector.Init(
new nsICharsetDetectionObserver() {
@Override
public void Notify(String arg0) {
found = true;
charset = arg0;
}
});
byte[] buffer = new byte[2048];
int length;
BufferedInputStream stream = new BufferedInputStream(new FileInputStream(file));
boolean done = false;
boolean isAscii = true;
while ((length = stream.read(buffer, 0, buffer.length)) != -1) {
if (isAscii) {
isAscii = detector.isAscii(buffer, length);
}
if (!isAscii && !done) {
done = detector.DoIt(buffer, length, false);
}
}
detector.DataEnd();
stream.close();
if (isAscii) {
charset = "us-ascii";
found = true;
}
if (!found) {
return null;
}
return charset;
}